In electrical or electronic systems, various individual system modules, for instance various electronic/electric assemblies/devices, various electronic/electric components, for instance various semi-conductor components such as integrated circuits, etc., various sub-components, provided in one and the same component or integrated circuit etc., communicate via a transfer medium such as a bus system.
A bus system may comprise one or more transfer lines. Bus systems can be used jointly by several, in particular by two or more than two components of a respective system.
Many conventional bus systems comprise several partial systems, for example a data bus that consists of one or more data lines, and/or an address bus that consists of one or more address lines, and/or a control bus that consists of one or more control lines.
In comparison to this, other bus systems are of a much simpler construction. For example, CAN bus systems (CAN=Controller Area Network) in general only comprise two or three lines (e.g., CAN_HIGH, CAN_LOW, and—optionally—CAN_GND (ground)).
Further, LIN bus systems (LIN=Local Interconnect Network) are known, which are even simpler. A LIN bus system 1 is shown in FIG. 1. In general, a LIN bus only comprises a single transmission line 2, to which a plurality of components 3a, 3b, 3c, 3d are connected. Consequently both useful data and address and/or control data are transmitted via the LIN bus transmission line 2.
LIN bus systems, in general, are based on a master/slave architecture, where one component (in FIG. 1, the component 3a) acts as a master, and the other components (in FIG. 1, the components 3b, 3c, 3d) act as slaves.
To establish a communication in a LIN bus system, each slave 3b, 3c, 3d of a LIN bus system has an own slave identification number or address (SL_ID_x, in FIG. 1: SL_ID_1, SL_ID_2, SL_ID_3). For a non-ambiguous assignment and data flow, each slave address should be unique in a LIN bus system. In other words, slaves can only be addressed independently if each of them has a unique slave address.
In some cases, especially when several identical components are connected to the same LIN bus system, it is of advantage not to use hardcoded unique slave addresses, since this would significantly increase the costs of logistics for ordering, assembly, stock etc. of the respective components. As a result, some LIN slave modules connected to a LIN bus system may not have unique slave addresses, but may have a common default address (in the following indicated as SL_ID_0).
In these cases, the functionality of such a module may be defined by its location in the LIN bus system (e.g., two similar door modules may be used, one for the front door, and one for the back door, etc.). Further, in these cases, a task of the master module is to identify the connected slave modules and to distribute unique slave addresses to those modules that have a common default address. This mechanism is called auto-addressing. An example for an auto-addressing method is, e.g., described in the U.S. 2005/0132109 A1.
However, common auto-addressing methods all have some drawbacks.
For these or other reasons there is a need for improved systems and methods to address devices connected to a bus system, in particular, a LIN-Bus.